T>12x. the total will be more than x multiplied by 12.
Area = width * height
since the window is 20 inches higher than the width:
width +20 = height
640 = width * width+20
640 = width^2 +20*width
width^2 +20*width - 640 = 0
width = 17.203
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Double Check
if width = 17.203 then height = 37.203
area = 17.203 * 37.203 = 640 square inches Correct!!
